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Old September 9th 11, 02:12 PM posted to rec.radio.amateur.antenna
dave dave is offline
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First recorded activity by RadioBanter: Jan 2009
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Default MFJ-868 SWR/Wattmeter

Jim Lux wrote:

On 9/7/2011 11:43 AM, dave wrote:
Jeff Liebermann wrote:


ohms-guesser). It therefore seems possible that the owner had
transmitted into the instrument (even though he denies it).


Why would anyone connect that antenna analyzer to a transmitter (unless
using the BNC?)


Oh.. that's an easy mistake to make. Bunch of coax with connectors
lying on the floor, hook up the wrong one. Hook a switch up
incorrectly. Coax switch without enough isolation (100W transmitter with
a 20dB isolation switch is a watt into the analyzer..)

Anyone who has never accidentally cooked a piece of test equipment just
hasn't been working long enough.


I remember frying a scope once measuring audio from a distant studio
that was on the opposite mains leg. It was a 50 cents a pound government
surplus scope, not my 465.

I would never leave an unterminated transmission line connected to my
transmitter. You always want 50 Ohms on that line when connected to
your XMTR.

I also would never "guess", (which is a kind of "assume"), unless I
really had to. I know I learned this the hard way.